class InventoryItem:
    def __init__(self, name: str, unit_price: float, quantity_on_hand: int = 0):
        self.name = name
        self.unit_price = unit_price
        self.quantity_on_hand = quantity_on_hand

    def __str__(self):
        return f'name = {self.name}, unit price = {self.unit_price}, quantity on hand = {self.quantity_on_hand}'


if __name__ == '__main__':
    obj = InventoryItem(name='123', unit_price='unit', quantity_on_hand=3.14)
    print(obj)
